Somehow I'm not positive Erlian thought this all the way through; it's not like having a unicorn trailing your every step is actually going to stop Tirian going out partying in the Garden District. (Especially on a couple of occasions when Jewel put his, uh, hoof down and Tirian shrugged and snuck out anyway. Look, Tirian had one of those childhoods.)

At best, another nature power, like the river gods or the spirits of the forest. At worst, pure historical figures. Something like that, anyway, even they probably aren't entirely certain.